Dwarf galaxies give clues to origin of supermassive black holes

Jan 08, 2014

Dwarf galaxy NGC 4395, about 13 million light-years from Earth, known to harbor a black hole some 300,000 times more massive than the Sun. It is a prototypical example of a small galaxy once thought to be too small to contain such a black hole. Credit: David W. Hogg, Michael R. Blanton, and the Sloan Digital Sky Survey Collaboration; NRAO/AUI/NSF.

(Phys.org) —Poring through data from a large sky survey, astronomers have found more than 100 small, dwarf galaxies with characteristics indicating that they harbor massive black holes feeding on surrounding gas. The discovery confounds a common assumption that only much larger galaxies hold such monsters and may help resolve the question of how such black holes originated and grew in the early universe.

"We've shown that even small galaxies can have massive black holes and that they may be more common than previously thought," said Amy Reines, of the National Radio Astronomy Observatory (NRAO). "This is really exciting because these little galaxies hold the clues to the origin of the first 'seeds' of supermassive black holes in the early universe," she said. Reines and her colleagues presented their findings to the American Astronomical Society's meeting in Washington, DC.

Black holes are concentrations of mass so dense that not even light can escape their gravitational pull. Nearly all "full-sized" galaxies are known to have supermassive black holes, millions or billions of times more massive than the Sun, at their cores. Until recently, however, smaller galaxies were thought not to harbor massive black holes.

Reines, along with Jenny Greene of Princeton University and Marla Geha of Yale University, analyzed data from the Sloan Digital Sky Survey and found more than 100 dwarf galaxies whose patterns of light emission indicated the presence of massive black holes and their feeding process.

"The galaxies are comparable in size to the Magellanic Clouds, dwarf satellite galaxies of the Milky Way," Geha said. "Previously, such galaxies were thought to be too small to have such massive black holes," she added.

In the nearby universe, astronomers have found a direct relationship between the mass of a galaxy's central black hole and a "bulge" in its center. This indicates that the black holes and the bulges may have affected each others' growth.

"Finding these small galaxies with massive black holes is an important step toward understanding how galaxies and black holes developed together," Greene said. "These dwarf galaxies are the smallest known to host massive black holes and can provide clues to how supermassive black holes get started in the first place," she added.

While today's larger galaxies hold black holes millions or billions of times more massive than the Sun, the dwarf galaxies in the new study have black holes roughly 100,000 times the Sun's mass. The supermassive and massive black holes are distinct from stellar-mass black holes—only a few times the mass of the Sun—that result from the collapse of a massive star at the end of its "normal" life.

Still unknown, the scientists said, is whether the massive black holes initially began as the remnants of extremely massive early stars or some other scenario of collapsing mass.

"Getting a good census of dwarf galaxies with massive black holes is an important first step to resolving this question," Reines said.

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User comments : 22

Why is it we see physicists develop computer models, demonstration videos, diagrams, countless formulas, etc, for the behavior of Black Holes, but very little research or modeling is done on the behavior of White Holes?

I realize that in some theories and interpretations of GR, the White Holes are just the "Other Side" of a black hole, but in other interpretations they may be objects in their own right. If we don't model these systems, how would we know if we were looking at them?

Unlike the "Broken laws of physics" white hole I mentioned the other day, a Relativistic White Hole need not spite out random crap. It probably spits out something uniform, like spherical progression of high energy photons, neutrinos, or other particles. It might even appear much like a Star under the right circumstances.

Yet we never see a "White Hole orbiting a neutron star" computer model. Why? Why?

Now I argued that a Relativistic White Hole which emits a uniform spherical, expanding shell of massive particles would eventually collapse into a black hole if the process went on long enough, or if the particle velocity was low enough for the cloud's mass to collapse again.

A short-lived white hole of such type might simply collapse back into a new Star. Which is to say, if it corresponded to a stellar mass black hole, and it emitted mass at a low enough rate, then a new star, perhaps having the appears of a neutron star or metallic star, might from from the ejecta on the other side, having a much lower density than the black hole the matter originally came from. One problem I'd see with this is re-producing atomic matter from the degenerate mass-energy state represented by the Black Hole.

I only mention this, because it could be an alternate source of the "Seed black holes," not to mention possibly an alternate explanation of some objects classified as Quasars.

So General Relativity boils down to one equation. On one side, you put stuff like mass and momentum and stress and strain, called the "Stress energy tensor." The other side of the equation is a "Curvature Tensor" that tells you how space-time will curve in the presence of that stress-energy tensor.

When we put in normal stuff like mass, we get stuff like black holes. But we can put in ridiculous things too, like imaginary masses (in the sense of sqrt(-1) imaginary), or more energy than exists in the universe, or other *unphysical* configurations into the stress-energy tensor, and we can construct a curvature of space-time that's associated with it.

So GR gives us plenty of *mathematical* solutions to space-time curvature that are none-the-less not thought to be physically plausible. White holes are one. As are wormholes and warp drives. There may be some way to create the energy configuration necessary, but... largely unlikely for many of these solutions.

Could "Dark Energy" be an effect created by the degenerate "Mass-Energy" of black holes "escaping," perhaps through another dimension of space-time, or though quantum tunneling or Hawking Radiation? Yet if "Dark Energy" is an expansion of space-time itself, then it's units actually should not be "Energy".

But some models predict that Black Holes "Stretch" out the dimensions of space-time, which at first appears contradictory, but supposing space-time is a non-energy entity there appears to be no good reason that space-time itself couldn't escape a black hole. So if the theory that space-time is stretched inside a black hole is true, then couldn't it be possible that the black holes in fact ultimately create "new" space-time outside their event horizons, which then has the effect of pushing stars and galaxies away from one another?

Think about it. No one put black holes in the mainstream models until there was observational evidence they actually existed. Until associated phenomena was actually observed there was nothing to model. They were paper and maths games.

People are doing just that (paper and maths) with white holes. But white holes can't take a place in models of the universe which reflect reality until there is some observation to put in the model. It would be like placing an unicorn on the tree of life in a high school biology class. The aim of physics to describe what we observe, the universe we live in, not every conceivable "far out pondering" and "day dream". That's the business of religionists, metaphysicists, philosophers, and science fiction writers.

Putting things into models that have no basis in observed phenomena or are not strongly inferred is usually a waste of effort and is a haphazard way of doing science.

Putting things into models that have no basis in observed phenomena or are not strongly inferred is usually a waste of effort and is a haphazard way of doing science.

I'd disagree.

If you have a model which is allegedly representative of reality, and you give it input, then it's output should also be representative of reality, unless the model is actually flawed.

The predictive ability of models in other contexts, such as chemistry, has allowed discovery of materials not previously thought about. Also, you are wrong about BH too, as they were considered and modeled for decades before their actual discovery.

I find that the strength of the Dark Energy phenomenon at distances of a few meters is comparable to the acceleration of 1kg of matter being acted upon by 2e-18 Newtons (assuming space-time behaved like a fluid being poured out, rather than a piece of rubber being stretched out), except Newtons wouldn't be the proper unit, but rather it's a change in space-time itself.

Zephir_fan

No one put black holes in the mainstream models until there was observational evidence they actually existed.

The only "observational" evidence is the presence of synchrontron radiation at galactic cores and the "only" option to explain such energies in gravitational theory is to create these abominations of science. Funny Peratt's models of galactic formation using interacting plasmas not only recreates the obvious morphology of galaxies of all ages but also recreates the observed radiation, rotation, and presence of HI clouds. It's obscene astrophysicists cannot see the obvious patterns, then again ignorance is a powerful foe.http://www.plasma...S-II.pdf

If space-time behaves like the "Rubber Sheet" analogy, at all, or perhaps just the "warped 3-d surface" concept, there should be a bias created by a form of "friction" from the spin (rotation) of orbiting objects, much like if you could imagine a ball spinning like a gyre on the surface of an inclined plane. Of course, we can't make a ball that spins in two axis at once, but if the "ball" were sliding on the plane across that plane, and rotating as well, right hand being high side and left-hand being low, then if the ball has a counter-clockwise spin as seen from above, it should have a bias to move to it's own right-hand side with respect to forward motion, like a hurricane does in the N. Hemisphere.

This would mean that planets with prograde rotation should have a right-hand bias in their orbits, over-shooting, while planets with retrograde spin with respect to their own orbits should have a left-hand bias in their orbits (i.e. tending to spiral inward or under-cut predicted path).

Zephir_fan

No cher, chou co, you would? That's how you end up the silly looking pointy cap on your head every day. You like the other peoples there making the funny faces at you?

The stupid head Ira is only an expert at saying nothing.

Returnering Lurker Skippy made that up all by yourself did you? I'm sure it means something and I know you are going to explain it to us but really wish you wouldn't no.

He has not time to make sock puppets to explain it to the ira who does not seem to understand anyone's posts no how many times already before. Let the smart peoples post without you interruptions with the nothingness from you, ira skippy.

Zephir_fan

If space-time behaves like the "Rubber Sheet" analogy, at all, or perhaps just the "warped 3-d surface" concept, there should be a bias created by a form of "friction" from the spin (rotation) of orbiting objects, much like if you could imagine a ball spinning like a gyre on the surface of an inclined plane.

Why would this friction not be time dilation and frame dragging that we have experimentally proven thus far? It's literally space-time being dragged around a high-mass object. I don't know if it would slow down the object's rotation any, but it's an observable effect that is similar to what you are referring to.

He has not time to make sock puppets to explain it to the ira who does not seem to understand anyone's posts....

... I'd give him two or one more try and then just let it go and do like the Ira does him, ridicule the foolishment that he thinks the science, eh mon ami?

Why does not the dumb boy zephir_fan Ira not simply tell him why he is wrong with the science facts about it? Do you not have the knowledge more so than the cranks to beat them at it, Ira? Is the Ira a stupid?

Zephir_fan

Why would this friction not be time dilation and frame dragging that we have experimentally proven thus far? It's literally space-time being dragged around a high-mass object. I don't know if it would slow down the object's rotation any, but it's an observable effect that is similar to what you are referring to.

Ordinary time frame dragging is caused by the central object, which biases the orbiting object forward faster than would be predicted by Newton, for example.

What I'm talking about is more like putting a lot of spin on a queue ball in billiards.

No one put black holes in the mainstream models until there was observational evidence they actually existed.

The only "observational" evidence is the presence of synchrontron radiation at galactic cores and the "only" option to explain such energies in gravitational theory is to create these abominations of science. Funny Peratt's models of galactic formation using interacting plasmas not only recreates the obvious morphology of galaxies of all ages but also recreates the observed radiation, rotation, and presence of HI clouds. It's obscene astrophysicists cannot see the obvious patterns, then again ignorance is a powerful foe.http://www.plasma...S-II.pdf

If you ignore the observed gravitational lensing, orbits of other objects around them and what happens when matter falls into them you mean?

If you guys still can't understand what I said, I'll try to say it again.

If you have an object moving through space along it's inertial path, and it has a spin axis not co-linear with the inertial path, then it's own spin should bias it's path slightly in the opposite direction of the leading-edge's spin motion.

This is NOT the same thing as orbital frame-dragging. There,the central object biases the orbiting object.

In the effect I'm talking about, the object should bias it's own path, very slightly, to one side of it's inertial path. The faster it spins, the bigger the bias should be.

This study shows, that the transition, from no central structure -> NSC -> SMBH, also involves the appearance, of intermediately MBH, in dE galaxies. Perhaps their is an evolutionary progression, with stars first "sinking" into the center of their host galaxy's central potential, so forming the cuspy NSC; and then "sinking all the way" into a central MBH ?

If so, then

(1) NSC would appear to brighten, over time, as more & more stars, sunk deeper & deeper, into the central potential region(2) eventually, NSC would "implode", vanish from view, leaving behind some central MBH

And still merger mania remains the preferred fantasy. Black holes are the source of growth, not the product of collapse...

http://phys.org/n...tly.html------------------------------------------------------------------"young galaxies can also grow, by sucking in cool streams of the hydrogen and helium gas that filled the early Universe, and forming new stars from this primitive material"

http://phys.org/n...022.html------------------------------------------------"The black holes in these young galaxies are much more massive, compared to the bulges, than those seen in the nearby Universe... the black holes started growing first"

Increasing accumulation, of primordial space gas, straight into the centers of such systems, could stimulate star formation, growing a NSC, until that NSC "implodes", into a MBH, which then grows into a SMBH, etc.

Why is it we see physicists develop computer models, demonstration videos, diagrams, countless formulas, etc, for the behavior of Black Holes, but very little research or modeling is done on the behavior of White Holes? ... Yet we never see a "White Hole orbiting a neutron star" computer model. Why? Why?

".. this region does not exist for black holes that have formed through gravitational collapse, nor are there any known physical processes through which a white hole could be formed."

It is arguable that you could model the big bang as a white hole (see the article) but other than that, they cnnot have formed subsequently.

Yet we never see a "White Hole orbiting a neutron star" computer model. Why? Why?

For the simple reason that this would already be a very specific scenario of a more basic one (viz: "white holes exist"). But since even that basic scenario does not seem to mesh with reality it's not useful to even look at more specific scenarios.

White holes - if they existed - would be VERY visible (unlike black holes, which are only visible through indirect methods: radiation produced when they feed and gravitational lensing).

Osteta

Increasing accumulation, of primordial space gas, straight into the centers of such systems, could stimulate star formation, growing a NSC, until that NSC "implodes", into a MBH, which then grows into a SMBH, etc.

Ah, statements presuming a fantasy as fact. This is the problem. Both articles support the inside-out growth model, where the grey hole is the source, not the sink. But you need to understand the model first, in order to fit the pieces. Lazy critics here only pick at isolated parts, and try to draw falsifying conclusions, in order to preserve peace with their Huge Bang fantasy.

A natural question arises from these observations: could such dwarf galaxy have been bigger or much bigger in the past and its central black hole swallowed nearby gas and stellar dust or even entire solar systems during the time, causing that galaxy to shrink significantly ? If affirmative, the next question could be: has such process occurred progressively during billions of (terrestrial) years or a catastrophic event happened at a galactic scale in a very short interval of time in the past and the galaxy shrank very fast ? Perhaps, in the past, there was a high density of black holes especially in the central region of that galaxy and when some threshold was reached, all these black holes collapsed into the central massive black hole of that galaxy, taking with them entire solar systems and the size of that galaxy dramatically diminished in a short interval of time. It would be interesting to know what would be the opinion of a specialist in astronomy about such scenario.

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